摘要
通过分析影响Y2 O3:Eu3+ 在 4 88nm激光激发下的5D0 →7F2 变温荧光发射强度的因素 ,建立起公式并对实验数据进行拟合 ,得到纳米晶的温度猝灭速率大于体材料的温度猝灭速率 .测得Y2 O3:Eu3+ 纳米晶和体材料的5D0 →7F2发射峰的变温线宽 ,通过内应力和量子限域效应对其不同进行了解释 .测量了Y2 O3:Eu3+ 在共振激发下的5D0 能级的荧光衰减时间随温度的变化 ,又利用公式对其进行拟合 ,得出了相比于体材料 ,纳米晶的辐射跃迁速率和无辐射跃迁速率均增大 ,但量子效率变小的结论 .然后利用晶格畸变和表面态效应对上述结论进行了解释 .
We analyze the factors which affect 5D 0→ 7F 2 luminescence intensity under the excitation of the 488nm light, and establish formulas accordingly. By fitting the experiment data, we find the temperature quenching rate of nanocrystals is faster than that of the bulk. We obtain the linewidth of 5D 0→ 7F 2 emission spectra of Y 2O 3: Eu 3+ at different temperature, and explain the difference between the nanocrystals and the bulk. using the internal stress and quantum confinement effect. Under the excitation of the 355nm light, we have measured the lifetimes of 5D 0 energy level of Y 2O 3: Eu 3+ , which change with temperature. According to the fitting results, we draw the conclusion that, in contrast with the bulk, both the radiation rate and non radiation rate of the nanocrystals have increased, while the quantum efficiency has decreased.We suggest that the possible reasons are lattice distortion and surface effect.
出处
《物理学报》
SCIE
EI
CAS
CSCD
北大核心
2002年第12期2875-2880,共6页
Acta Physica Sinica
基金
中国科学院百人计划 (批准号 :Z0 1M2 0 )资助的课题~~
